Signaling system



T. H. NEELY SIGNALING SYSTEM 3 Sheets-Sheet 1 Filed Sept. 18, 1935#VVE/WOR 7'. H. NE EL? Dec. 29, 1936. T. H, NEELY 2,065,905

SIGNALING SYSTEM Filed Sept. 18, 1955 3 Sheets-Sheet 2 TOLL SEL ECTOR//V VEN TOR AHORA/5y Der- 29, 1936. T. H. NEL-:LY

SIGNALING SYSTEM 3 Sheets-Sheet 3 Y Nugl Filed Sept. 18, 1935 By IArroR/vr Patented Dec. 29, 1936 SIGNALING SYSTEM Application September18, 1935, Serial No. 41,008

5 Claims.

This invention relates to remote control, i. e., operation or release ofelectric devices, over a telephone line or other circuit, by means atthe receiving end of the line controlled by momentary line impulses,either open or closed circuit, initiated at the control end of the lineby the respective operation and release of functional switching devices,as, for example, simple circuit closing keys.

More speciiically, the invention relates to means at the control end ofthe line, responsive to closure oi a key or other circuit closing devicefor initiating transmission over the line oi a predetermined number ofshort impulses, either open or closed circuit, and means at the distantend of the line for receiving and translating these impulses to operatea desired device, as

for example, a relay, corresponding to the key operated at the controlpoint, said means at each end of the line also being adapted tosimilarly initiate and receive a predetermined number of similarimpulses (usually one) when the control key is restored to release therelay.

One embodiment of the invention wherein a feature of the presentinvention Aresides consists of a toll dialing system comprising a trunkline extending between a toll dialing operators position at one end andan automatic or machine switching oflice at the other, said trunk linebeing arranged for sol-called composite dialing, i. e., arranged fortransmitting dial impulses and other signals and for holding anestablished connection over a single conductor. in such a system it maybe required to perform auxiliary functions at the automatic oice undercontrol of the toll operator after the desired connection has beenestablished by dialing and is being held such, for example, as startingringing on the selected line, reringing, or connecting coin potential ofeither one polarity or the other tothe selected line for the purpose ofcollecting or refunding a coin at the automatic subscribers station.

Under such conditions, in accordance with the present invention, thetoll operators cord circuit is provided with the usual ringing key, coincollect key and coin return key and all so arranged as to operaterespective relays in the outgoing end of the toll line to which theoperators cord circuit is connected.

In the outward end of the toll line circuit means, initiated byoperation of any one of these relays, is also provided for momentarilyinterrupting the closed composite circuit a predetermined number oftimes depending on the relay operated thereby momentarily releasing andreoperating the usual polarized relay at the automatic office end oi theline a corresponding number of times. At the automatic office end of theline this release and reoperation of the polarized relay causestranslating means thereat to select and operate a particular one ofseveral reiays depending upon the number of times the composite circuitis opened and closed, which particular relay is adapted when operated toperform the desired function, as tor example, starting ringing on theline selected by a previous dialing operation.

After the relay at the automatic office is operated it is held operatedunder control of the) impulse translating means at that end of the line.

-When the toll operator releases the operated key the interrupting meansat the outgoing end of the line again functions to momentarily interruptthe composite circuit once only thereby causing a corresponding releaseand reoperation of the polarized relay at the distant end of the linewhich monetary release causes the translating means thereat to respondand release the operated relay.

in general, regardless of the path over which the impulses-aretransmitted, the invention may be broadly stated as an arrangementwhereby the operation of a functional circuit closer initiates thetransmission of a predetermined number oi momentary line impulses of anypredetermined character to cause the selection and operation of acorresponding electromagnetic device at the distant end oi the line andwhereby the release of the circuit closer initiates the transmission oia single or predetermined number of impulses over the line which willcause release of the device.

The invention will be understood from the following description whenread in connection with the accompanying drawings.

Referring to the drawings, Figs. l, 2 and 3, when taken in the orderillustrated in Fig. 4, disclose a portion oi a telephone systememploying a toll dialing trunk circuit which embodies the remote controlsignaling features of this invention for controlling the ringing andcoin disposal at the subscribers station.

Fig. 1 shows such portions of the toll switchboard end of a tollswitching trunk circuit arranged for composite signaling, and also suchportions of a toll operators cord circuit, as area required toillustrate the features of this invention;

Fig. 2 shows the essential portions of the stepby-step oce endrof thetoll switching trunk the other end of which trunk is shown in Fig. 1;and

Fig. 3 shows a step-by-step toll connector circuit the function of whichis to establish connections to subscribers stations one of which,station S, is also shown in Fig. 3. k Since this invention relates tothe control of ringing and coin disposal at a Vsubscribers station, allof which takes place after connections between the toll switchboardoperator and the called subscriber have been established, it will beassumed that the tool operator by means of dial riti of the cord circuitOC has dialed Vthe number of the called station S and thereby Ycausedthe toll connector circuit shown in Fig. 3

to function, in a manner well known to the art, and connect its brushes3|,2 to connector bank terminals 3|3 thereby establishing connectionsover line 3|5 to the subscribers station S.

With connections established to station S Vas set forth above thefollowing conditions obtain in the trunk circuit shown in Figs. l and 2and in the connector circuit shown in Fig. 3. Dialing having beencompleted, relay H03 of the oper- Vators cord circuit OC is in itsunoperated position. Plug |04 of cord OC has beenpreviously insertedinto jack |05, thereby operating relay |0l-to battery through resistance|06. Relay |01, operated, operates relay |08 locally. Relay |03,operated, connects battery throughresist-Y ance V| and over its lowerfront contact to the junction of the two windings of the compositesignaling relay l2 thereby causing the operation of composite signalingrelay 20| at the step-bystep end of the trunk. Relays |09, l I0 and |38Vof Fig. l provide for transferring the control conductors to theringing, coin collect and coin return control relays at the conclusionof dialing and function as set forth in the subsequent paragraphs.

When the toll operator initiates Va call by inserting plug |04 into jack|05 the connection to station S is established by the toll connectorshown in Fig. 3 which functions under control of dial pulses from dialMl. 'Ihe manner in which these pulses are transmitted over the compositesignaling trunk and also the manner in which the toll connector circuitfunctio-ns are well known to the art and since this is not a feature ofthe invention no detailed description thereof will be given. However,since the dial impulses areV transmitted to the trunk over the ringconductor of the operators cord OC and since the coin collect and'coinreturn impulses are also transmitted over the same conductor, means isprovided in the toll switchboard end of the trunk for transferring fromthe dialing portion of the circuit to the ringing and coin disposalportion at the conclusion of dialing. This is accomplished by relays|09, ||0 and |38 in the following manner: With plug |04 in jack |05 theoperation of the toll operators dialing key (not shown) operates thecord circuit relay |03. A circuit is thereuponcompleted from batterythrough resistance |39, upper front contact Vof relay |03, backcontactof ringing'key I6, tip

' conductor of cord OC, tip of plug |04 and jack |05, left upper windingof repeating coil l|2I,

upper back contact of relayV H0, to ground through the winding of relay|09. Relay |09 operates and completes the circuit for relay |38 Vwhichoperates in Ya circuit from` ground through Vits Winding and over itsnormally closed Contact,

yupper front Contact of relay |68.

upper front contact of relay |058.V Relay |38 locks `over the lower backcontact of relay ||0, to theV same battery over the upper front contactof relay |08 and prepares an yoperating circuit forV relay H3. Theportions of the trunk circuit in-V thereupon releases and operates relay||0 in a circuit from ground through the winding of relay H0, over thelower front contact of relay |38, back contact of relay |09, to lbatteryover the Relay I0', in operating, locks over its lower front contact Vtothe battery over the upper front contact of relay |08, opens the lockingYcircuit for relay |38 which releases; transfers the'tip conductor ofthe trunk, through the left upper winding of repeating coil |2|, fromthe winding of relay .|09 to the lower or operating winding of theringing control relay H9; and closesthe ring conductorY the t0nSwitchboard end of the trunk from the Y Y dialing phase to the ringingand coin control phase. Y

Referring now to Figs. 2 and 3, the initial application of battery tothe windings of the composite signaling relayrl I2 of Fig.V V1 prior todialing caused the operation lof composite signaling relay 29| of Fig. 2in a manner Well known to the art. The operation of relay 20| causes atoll selector circuit (represented by block 23.0)` to be, seized.Subsequent Ydialing by the toll operator causes the toll selectorcircuit and the toll connector circuit shownin Fig. 3 to function, thetoll connector Vcircuit establishing connections to Vthe'called stationS in a manner well known to the art. Dialing having been completed, the

following conditionsV cbtainrin the step-by-stepY oiice end of the tooltrunk: Relay 20| isV operated as set forth above. Relay 204 is opera-tedin a circuit from battery through resistance 2|2, winding of relay 204,to a ground on conductor 2| 0, this ground being returned from tollselector circuit upon i-ts seizure. Relay 202 is operated in a circuitfrom ground over the upper middle front contact of relay 204, armatureand Contact of relay 20|, windingof relay 202, lower middle frontcontact of relay 204, to battery through resistance 236. Relay 203 isoperated in a circuit from battery through its lower winding, over thefront contact of relay 202, to the ground over conductor 2|0.

In the toll connector circuit shown in Fig. 3 the following conditionsobtain following the establishment of. connections to station S.Assuming that the called station S was idle, upon the connection ofbrushes 3|2 to terminals 3|3, under control of vertical stepping magnet309 and rotary magnet 3|0,'in a manner well knownY to the art, a circuitwas completed from'batte'ry through the Winding of the cut-off relay3M,V sleeve terminal and brush, back contact of relay 307, upper innerback contact of relay 30S, upper front contact of relay 30| through theup# per winding of relay 303, to ground over conduc-Y Ator 2li! suppliedby the toll selector circuit. Re-

lay 323 operated and locked through its lower winding and over its lowerinnerfront contact to ground on conductor 2I0. The operation of relay303 opened the circuit through the windings of relay 30| which released.Relay 323 also connected ringing current from the source SII to theupper front contact of relay 303 and, in addition, opened a lockingcircuit for relay 322, this circuit being traceable from battery throughthe lower winding of relay 302, lower inner front contact of relay 302,lower inner back contact of relay 306 and over the lower outer backcontactof relay 303, to ground over conductor 2III from the tollselector circuit. Relay 302 remains operated, however, under control ofthe toll switching trunk circuit in a circuit traceable from batterythrough its lower winding and over its lower inner front contact, lowerinner back contact of relay 306, conductor 2| I, upper inner frontcontact of relay 20@ of Fig. 2, upper inner back contact of relay 209,to ground on conductor 2I0 from the toll selector circuit. Ringing ofthe called station S by the toll operator under control of the remotecontrol selective signaling system which comprises this invention nowtakes place in the manner described in subsequent paragraphs.

The operation of the cord circuit ringing key IIB operates relay H in acircuit from ground through resistance |20 and the lower winding ofrelay H9, over the upper inner front contact or relay ||0, left upperwinding of repeating coil I 2|, tip conductor of the trunk, tip springof jack |05 and tip element of plug |04, front contact of ringing key II0, to battery. Relay IIS, operated, operates relay |22 in a circuitfrom battery over the upper back contact of relay |23, winding of relay|22, back contact of relay I2, to ground over the lower outer frontcontact of relay I I9. Battery, through the winding of relay |23, isconnected over the lower inner front contact of relay IIS), to the thirdbank terminal of the selective control switch IIS the function of whichwill later be described. Relay |22, in operating, locks relay I I0through the upper winding of that relay, and operates relay |25 frombattery through the winding of relay |25, lower front contact of relay|22, back contact of relay |24, to ground over the lower outer frontcontact of relay II9. Relay |25, in operating, locks directly undercontrol of relay IIIl, and connects a low frequency alternating currentfrom the source |26, over its upper outer front contact, to the windingof relay |2'I. Relay I2`I, which is a polarized relay, follows thealternating current pulses, its armature intermittently closing groundthrough the winding of rotary magnet |28 which is associated with switchIIS. Brush |29 of switch H3 advances one step for each closure of thecircuit through rotary magnet |20. As brush |21 contacts the secondterminal of switch II3 the ground on the brush short-circuits thebattery through resistance III which has been connected to the junctionof the two windings of the composite signaling relay H2 thereby causingthe composite signaling relay 20| at the step-by-step end of the trunkto release and function as will later be set forth. When brush |29leaves the second bank terminal of switch H3 to advance to the thirdbank terminal it removes the short circuit from resistance I I Ireconnecting battery to the windings of relay |I2 and therebyreoperating relay 20! at the step-by-step end of the trunk. When brush|29 contacts the third bank terminal of switch II3 relay |23 operatesover the lower inner front contact of relay IIIl and locks over itsfront contact to ground over the lower front contact of the oir-normalsprings |30 these latter springs having operated as soon as switch II3took its first step. Relay |23, in operating, opens the circuit throughthe winding of relay |21 to prevent any further stepping of switch I I3,and also opens the circuit through the winding of relay |22. Relay I22,in releasing, opens the locking circuit through the upper winding ofrelay IIe, this latter relay remaining operated over its originaloperating circuit through its lower winding should the ringing key ofthe chord circuit still be operated.

When the toll operator releases ringing key IIS relay IIS releases inturn releasing relay |25. Relay i212 thereupon operates in a circuitfrom battery through its winding, over the upper contacts of theoperated off-normal springs |30, to ground over the back contact ofrelay |25. Relay I2I locks over its inner front contact to ground overthe lower contacts of springs |36, energizes release magnet ISI, andalso shortcircuits the battery through resistance III thereby causing asecond release of the composite signaling relay 20| at the step-by-stepend of the trunk. The function of this second release of relay 20| willbe set forth later. Release magnet ISI energized causes the switch I I3to restore to normal at which time the off-normal springs |30 alsorestore. The opening of the contacts of spring ISI) release relay |24which in turn opens the circuit through the winding of release magnetI3I. Two single impulses have been transmitted over the compositesignaling circuit from the toll switchboard end of the trunk to thestep-by-step omce end of the trunk. The first single impulse controlsthe ringing current at the step-by-step oice while the second singleimpulse serves to restore the remote control signaling circuit at thatoffice to normal so that this said signaling circuit may be receptive tosubsequent coin disposal signals, these operations taking place in themanner hereinafter described.

Referring now to the step-by-step office end or the trunk shown in Fig.2, the rst release of the composite signaling relay 20|, in response tothe shcrt-circuiting of the battery at the windings of relay II2 aspreviously described, opens the circuit through the winding of relay202. Relay 202 releases and operates relay 2I'I and energizes rotarymagnet ZEG of switch ZIB in a circuit traceable from battery through thewindings of this said relay and magnet in parallel, over the backcontact of relay 222, lower inner front contact of relay 20d, backcontact of relay 202, and over conductor 2|@ to ground supplied from.the toll selector circuit. Relay 2Il, in operating, locks over its frontcontact to the ground over conductor 2|0 under control of the lowerinner front contact of relay 204 and the back contact of relay 202, andopens the circuits to the brush 2I9 of switch 2I8 and to the winding ofrelease magnet 220. Rotary magnet ZIE, energized, causes brush 2I9 toadvance and contact the rst terminal of switch 2m. As brush 2|9 movesout of its normal position the oir-normal springs 22| close theircontacts and complete a circuit from ground on conductor 2I0, lowercontacts of springs 22|, to battery through the lower winding of relay222. Relay 222 operates and closes, in part, the circuit to releasemagnet 220, relay 222 remaining operated through its lower winding aslong as switch 2 I8 is in any position other than normal.

When relay 20d reoperates following the first signaling pulse relay 202Yreoperates and opens the locking circuit for relay 2|1. Relay 2|1releases and operates relay 209 in a circuit traceable from batterythrough the Winding of relay 209, rst terminal of the bank of terminalsof switch 2| 8, brush 2|9, back contact of relay 225, lower back contactof relayV 2I1, front contact ofrelay 202, to ground supplied from thetoll selector circuit (not shown) over conductor 2|0. Relay 209,operated, opens the `circuit between conductors 2|0 and 2H therebyremoving ground from conductor 2H and' also connects ringing currentfrom the source 224 to the tip and ring conductors 205 and 206 towardthe toll connector circuit over back contacts of Vrelays 208 and 201.V Y

Referring now to the toll connector circuitV shown in Fig. 3, aspreviously set forth'relays 302 and 303 are operated up to this time,relay' 302 being locked operated through its lower' winding to theground supplied over conductor 2H under control of the back contact ofrelay 209, while relay 303 is locked operated over its lower winding toground supplied over conductor 2|0 from the toll selector circuit. Theremoval of ground from conductor 25| by the' operation of relay 209 asset forth above causes relay 302 of the connector circuit toV release.Upon the release of relay 302 a circuit is completed from ground throughthe pick-up interrupter 305, over the lower outer front contact of relay303, lower normally closed contacts of relay 304, lower outer backcontact of relay 302, to battery through the winding of relay 304. Whenthe brush of pick-up interrupter 305 contacts a conducting commutatorsegment relay 304 operates and locks over the lower outer back contactof relay 302 and over its own lower front contact to ground overconductor 2|0. Ringing current is thereupon connected to the calledstation S in a circuit traceable from the ringing current source 3|6,over the upper middle front contact'of relay 303, upper front contactofrrelay 304, upper winding of relay 302, next-to-outer upper frontcontact of relay 303, upper and lower inner back contacts of relay 302,lower outer back contact of relay 306, ring conductor, ring brush ofbrushes 3|2, ring terminal of connector bank terminals 3|3, ringconductor of line 3|5, through station S, tip conductor of line 3|5, tipterminal and brush of terminals 323 and brushes 3|2, tip conductor ofthe connector, upper Vouter back contacts of relays 305 and 302, toground over the upper outer front contact of relay 303. Y Y

When the subscriber at station S answers and removes the receiver fromthe switchhook relay 302 operates on the ringing current through itsupper winding suiciently to close its lower inner front contact andthereupon completely operates and locks through its lower windingrin apreviously traced circuit to ground over conductor 2| ground having beenreplaced on conductor 2H by the trunk circuit in the manner which willbe set forth in the succeeding paragraphs. Relay 302, in operating,removes Y the ringing current from line 3|5 andopens the Y lockingcircuit for relay 304 which latter relayk thereupon releases. y A

The operation of relay 2097at the step-by-step Y end of the toll trunk,in addition to opening the ground from Vconductor 2H to cause theconnector circuit to function and ring the called station as set forthabove, also connects ringing current from the source 224 to one side ofcon Ydansers, V226 and 221, the other side of. which condensers connectto the right windings of repeating coil 223. A portion of the ringingcur- Y rent is induced in the left windings of coil 223 and extends overconductors H4 and H5,

Ythrough condensers |42 and |43, to the rightV When the tool operatorreleases ringing key l0 and relay |25 releases, battery throughresistance to the windings of relay H2 is shortcircuited as previouslyset forth, resulting in the transmission of a single restoring pulse tothe step-by-step end of the trunk and causing the release of relay 20|at that end of the trunk. Relay 20|, releasing, releases relay 202 whichcompletes a circuit from ground over conductor 2|0, back contact ofrelay 202 lower inner front contact of relay 204, upper outer frontcontact of relay 222, and over the upper back contact of relay 2|1,through the windings of release magnet 220 and relay 225 in parallel, tobattery. Relay 225 operates, locks over its front contact and the lowercontacts ofsprings 22| to ground over conductor 2 |0, maintains thecircuit through the winding of magnet. 220, and opens thev op'V eratingcircuit Vfor relay 209. Relay 209 releases, removing ringing currentfrom condensers 226 and 221 and again closing the circuit betweenconductors 2|0 and 2H thereby permitting relay 302 of the connectorcircuit to lock after operating at the time the called subscriberanswers as has hereinbefore` been set forth. Release Vmagnet 220,energized, causes the'brush 2|9 ofrswitch 2|8 to restore to its normalposition at which time the off-normal springs 227| also restore andthereby open the locking circuits for relays'222V andl 225 and magnet220. thereby restore the signaling circuit to normal.

Supervision g After the connector relay 302 operates vfollowing theanswer Vby the called subscriber supervisory relay 2|3 :at thestep-by-step end of the trunk circuit operates in a circuit from groundthrough its upper winding, over the upper outer front contact ofrelay204, right upper winding of repeating coil 223, upper outer backcontacts of relays 209, 208 and 201, tip conductor 205, uppernext-to-inner front contact of relay 303, upper outer front contact ofrelay 302, upper outer back contact of relay 30S, tip conductor of line3|5, through the subscribers sta- Relays 222 and 225 release andY tionS, ring'conductor of line 3|5, lower outer Y back contact of relay 306lower outer front contact of relay 302, lower middle front contact ofrelay V303, ring conductor 206, lower back contacts of relays 208, 201and 209, right lower winding of ,coil 223, lower outer front contact ofposite signaling relay 20| and connects battery, to this pointinsteadthereby causing ,the com- Vposite signaling relay H2 atrthe'trollswitch-Y board end of the trunk to operate for supervisory purposes.This supervisory circuit has not been shown since it is not a feature ofthisU invention and functions in a manner well-known to the art. Y

Rerznging by toll operator Should the operator at the toll switchboarddesire to rering the called station after the connection has been set upas hereinbefore set forth the manner in which the ringing control relay29 at the step-by-step end of the toll trunk is operated by the remotecontrol signaling circuit of the trunk under control of the operation ofringing key H6 of the cord circuit OC is identical with that previouslydescribed. From the point of the Operation or" relay 2li@ however themanner in which station S is rung diiers since both relays 2|3 and 2Mare operated, the subscriber at station S having answered in response tothe initial ringing by the toll operator. The upper outer front contactof relay 2|4 parallels the upper inner back contact of relay 20S and,upon the operation of relay 2| 4 when the subscriber answers, conductor2|| is therefore grounded from conductor 2|@ independently of the backcontact of relay 269. The operation of relay 209 during reringingtherefore does not release the toll connector relay 302, the release ofwhich latter relay originally connected ringing current to line 3|5 ashas previously been set forth. Since relay 3532 remains operated ringingcurrent is applied to line 3|5 in this instance from source 22d, overfront contacts of relay 209, back contacts of relays 2% and 201,conductors 205 and 20B, front contacts of relays 303 and 302, and overthe back contacts of relay SUS.

Coin collection When the toll operator is ready to collect coins atstation S she depresses the coin collect key of her cord circuit OCwhich causes the remote control selective signaling circuit of the tolltrunk to function and apply coin collect potential over line 3|5 in themanner set forth in the subsequent paragraphs.

The operation of coin collect key completes a circuit from battery,through resistance |32, front contact of key ring of the plug im andjack |85, left lower winding of repeating coil |2|, upper outer frontcontact of the previously operated relay H0, through the winding ofrelay |313, through the two windings of relay |33 in series, to groundthrough resistance |35. The coin collect control relay |33 operates overthis circuit but the marginal coin return control relay |35 does notoperate due to the limited current ow caused by the inclusion ofresistance |32 in the circuit. Relay H3, operated, locks through itsupper winding to its previously traced operating battery, and operatesrelay |36 in a circuit extending over the back contact of relay |34.Relay |35, operated, operates relay |22 in a circuit traceable frombattery over the upper back contact of relay |23, winding of relay |22,back contact of relay |24, to ground over the lower outer front contactof relay |36; locks over its upper front contact to ground over theupper front Contact of relay |22 as soon as relay |22 has operated; andconnects the winding of relay |23 to the seventh terminal of theterminal bank of switch H3. Relay |22, in operating, operates relay |25over a previously traced circuit. Relay |25 locks over its upper innerfront contact to ground over the lower outer front contact of relay |35and connects low frequency alternating current from the source |25, overits upper outer front contact and the lower back contact of relay |23 tothe winding of polarized relay |21. Relay |21 follows the alternatingcurrent pulses, its armature intermittently connecting ground to thewinding of rotary magnet |28 associated with switch it. Each time thatmagnet |28 is energized it causes the brush |29 to advance one step,progressively contacting the bank terminals of switch |3. At thecompletion of the seventh step of brush |29 a circuit is completed fromground on brush |29, over the seventh bank terminal of the switch, lowerinner front contact of relay |35, to battery through the winding ofcut-orf relay |23. Relay |23 operates and locks over its iront contactto ground over the lower contacts of the off-normal springs |39 whichoperated upon the first step of the brush or" switch H3. The operationof relay |23 also opens the circuits through the windings of relays |22and |21, both of which release. The release of relay |2| prevents anyfurther stepping of switch H3, while the release of relay |22 opens thelocking circuit for relay |32. If the toll operator has restored thecoin collect key |'s' of the cord circuit relay |33 therefore releasedand opened the operating circuit for relay |36, this latter relaythereupon releasing when its locking circuit is opened by the release ofrelay |22. Relay |35, in releasing, releases relay |25. Relay |24thereupon operates in a circuit from ground over the back contact ofrelay |25, upper contacts oi the operated offnormal springs |32, tobattery through the winding of relay |24. Relay |22 operated, locks overits lower inner front contact to ground over the lower contact ofsprings |32, and energizes release magnet |3| which in turn causes thebrush |29 of switch H3 to restore to normal. With switch I3 normalsprings |33 restore and release relay |22. The release of relay |2|opens the circuit through the winding of release magnet |3| therebyrestoring the selective signaling circuit to normal.

As brush |29 advances over the terminals of switch ||3 during its sevensteps as detailed in the preceding paragraph, the ground over the brushshort-circuits the battery supplied through resistance to the windingsof relay ||2 as the brush contacts the second, fourth and sixth bankterminals. This results in the transmission of three signal pulses tothe step-by-step end of the trunk which functions as will subsequentlybe set forth and applies coin collect potential to the called stationline. During the release of the signaling circuit at the tollswitchboard end of the trunk, the operation of relay |24 also connectsdirect ground to the junction of the windings of relay |2 therebyshort-circuiting the battery through resistance and causing a singlerestoring pulse to be transmitted to the step-bystep end of the trunkwhich thereupon functions as will be described hereinafter.

Referring now to Fig. 2, the three signal pulses transmitted from thetoll switchboard end of the trunk for controlling the application ofcoin collect potential to the called line cause the composite signalingrelay 20| to release and reoperate three times. Relay 222 releases andreoperates in unison with relay 22| and causes rotary magnet 2||5 to beenergized three times, over a previously traced circuit, thereby causingbrush 2|9 of switch 2|S to be advanced to contact the third terminal ofthe switch bank. Relay 2 l operates in parallel with rotary magnet 2|@and functions as previously set forth. Offnormal springs 22| operate assoon as brush 2|@ leaves its normal position and operate relay 222 overa previously traced circuit.

, ductor 250. Relay 208, in operating, applies negative coin collectpotential to the line 3|5 of station S in a circuit traceable-fromnegative potential, through alarm lamp` 223, over the Yupper inner frontcontact or relay 20B, winding of relay 230, upperV back Vcontact ofrelay 233, to the V'conductor ofthe line.

ring conductor 203 which extends over front contacts,V ofconnector'relays 303 and302 and over a lower back contact of relay 30Bto the ring This coin collect potential, traced to the Vupper backcontact of relay 233 also extends from that point, over the lowerouterand upper outer front contacts of relay 200' and o vfer the upperback contactV of relay 201 to the tip trunk conductor V205 and fromthere extends to the tip of the called line Yover a previously tracedcircuit through the connector circuit. A circuit is also completed fromground through interrupter 23|, over the lower inner front contact ofrelay S, lower back contact of relay V233, to battery through the upperwinding ofV relay 232. Relay 232 operates and extends its operatingground to theupper winding of relay 233. RelayY 230 operates in serieswith the coin magnet (not shown) Yat the subscribers station S andconnects ground tothe other end Y ground for the 'lower windingof relay233 also ductor of the trunk extending' towardsV the Vtoll operator.VThe left winding of coil23 is connected to battery andalso to groundthrough the brushes of interruptor 231. A tone Vis thereby inducedthrough coil 238 and condenser 234'rto the toll switchboard operator asan indication that coin potential islbeing applied to the called stationline.

' Upon the first open period of interrupter 23|Y relay 223 operatesthrough its upper winding, in

V series withvthe upper winding of relay '232, to

ground over theV upper front contactY of relay 230. 'Y Relay 232 holdsin this circuit through its :upper winding and over its upperinner'front contact. Upon the next Vclosure of interrupter 23| relay 233holds through its lower winding and over its lower front contact. Thisholding extends over the lower front contact of that relay and over thelower front contact of relay 232 to battery through the lower winding ofVrelay 232. TheV two windings of relay 232 are wound diierentially, thatis, they exert'opposing forces, and, Ysince they are both now energized,relay 232 releases and opens the circuit through/the upper winding ofrelay 233, this 'latter relay holding through its 'lower winding as'justset forth. The release of relay 232 also removes the negative coincollect potential from conductors 205 and 2055Y and therefore from theline 3|5 which extends to station S. Relay `230V remains operated uponthe release of relay 232 in a circuit'traceable from ground over itsupper front contact, upper front contact of relay 233, throughresistance 235, closed contacts. of the make-before-break contacts ofrelay 232, winding of relay 230, upper inner front contact of relay 208,to the negative vcoin collect potentialV through lamp 228. The next openperiod of interrupter 23| opens the holding circuit through the lowerwinding of relay-233 which thereupon releases. Both relays 232 and 233are now unoperated after having caused the application of one pulse ofcoin collect potential to the called'A station line. When the nextconducting segment of the commutator of interruptor 23| contacts thebrush of that interruptor relay 232 again` operates over the previouslytraced circuit and again connects the negativecoin collect potential tothe called line. period of Vinterruptor 23| through its upper kwindingin series with the upper winding of relay 232 as previously set forth.Relay 232 releases Vwhen its lower winding is energized upon thenext'closure of interrupter 23| and again removes the coin collectpotential from the line. This cycle of operation and release of relays232 and 233 with its resultant intermittent application of coin collectpotential to the-line continues in the manner described as long as theoperator at the toll switchboard continues to hold the coin collect keyof cord circuit OC operated.

After the elapse of an interval Vdeemed sufllcient for the collection ofthe coin or coins at the subscribers station the toll operator releaseskey of relay |36 releases relay |25. Relay |24 there- Upon the next openrelay 233 operatesv upon operates in a circuit from battery through'`its winding, over the upper contacts of olf-normal springs 130Yassociated with'rthe operated switch H3, Vto ground over the back.contact-of relay |25. Relay |24, Vin operating, locks over its innerfront contact and over the lowercontacts of springs |30, energizesVrelease, magnet 1 |31 and, in addition, short-circuits the batterysupplied through resistance to the windings of the composite signalingrelay |I2 thereby 'Y causing a` release signal to be transmitted tothestep-by-step onice end of the trunk which thereupon functions as will beset forth later. Release Y magnetV |3l, being energized, causes thearmature |29 of switch V||3 to restore to Vits normal position at whichtime the off-normal springs |30 also restore to their unoperatedposition.

The restoring ofksprings |30 opens theoperat- Ving and locking circuitsfor` relay- |24 which thereupon releases and restores the tollswitchboard end of the trunk to the condition` in whichY of theV trunk.The release of relay 20| releasesV relay 202. Release magnet 220 andYrelay 225 thereupon energize inV a circuit from battery through theirrespective windings in parallel, over the upper back contact of relay21T, upper outer contact of relay 222, lower inner front Y Contact ofrelay 204, back contact of relay v202, 7 5;

to ground over conductor 2li), previously traced. The release of relay222 also opens the circuit through the winding of relay 2&8 whichreleases and removes the coin collect potential from conductors 2li-5and 263e should relay 232 be in its operated position at this time.Relay 225 operates, locking over its iront contact and over the lowercontacts of the operated off-normal springs 22| to ground over conductor2in, and maintaining the energizing circuit for release magnet 22%. Theenergizing of release magnet 229 causes brush 229 of switch 2|8 torestore to its normal position at which time the oir-normal springs 225also restore to normal and thereby release relay 225 and open thecircuit through the winding of magnet 226. The aforementioned release ofrelay 223 opened the circuit from the brush of interruptor 23| to relays232 and 233 which, if operated, release. Relay 235i also releases uponthe release of relay 268. The coin disposal portion of the trunk circuitis now normal and the trunk circuit is in the condition whereconversation between subscribers or between operator and subscriber mayensue.

Coin return II", instead of collecting coins at station S as set forthabove, it is desired to return the coins deposited at that station thetoll operator depresses the coin return key H8 of her cord circuit OCthereby connecting direct battery over the contacts of that key and overa previously traced circuit through the windings of relays |312- and |33in series, through resistance |35 to ground. Relay i553 operates andmarginal relay i511, which did not operate when the coin collect key Hlof the operators cord circuit was depressed due to the inclusion ofresistance i3d in the circuit at that time, now also operates. Relays|33 and |3, operated, lock in series through the upper winding and overthe lower front Contact of relay |33 to ground. Relay i3? operates frombattery through its winding and over the upper iront contacts of relays|355 and |33 to ground. Relay |22 thereupon operates in a circuittraceable from battery over the back contact of relay |23, winding ofrelay |22, back contact of relay |215, to ground over the lower outerfront contact of relay |31. |22, in operating, supplies a holding groundfor relay |31 over its upper front contact and also completes a circuitfrom battery through the winding of relay |25, lower front contact ofrelay |22, back contact of relay im, to ground over the lower outerfront contact of relay 31. Pselay 25 operates, locks over its upperinner front contact to ground over the lower outer front Contact ofrelay |3l, removes the ground from the upper Contact of the oil-normalsprings |38 and, in addition, completes a previously traced circuit fromthe low frequency alternating current source |26 through the winding ofpolar'- ized relay |21 thereby causing relay |21 to operate and releasein unison with the alternating current and intermittently complete thecircuit through the winding of rotary magnet |23 of switch H3.

Under control of relay S27 rotary magnet |28 causes brush |29 of switch||3 to advance, one step at a time, over the associated bank terminals.When brush |29 contacts terminal No. 5 a circuit is completed fromground over the brush and the bank terminal and over the lower inneriront contact or" relay |37 to battery through the winding of relay |23.Relay |23 Relay operates and locks over its front contact to ground overthe lower contacts of springs |30, these springs having operated as soonas brush 22 advanced out of its normal position. The operation of relay|23 opens the circuit through the winding of relay l2'l therebypreventing any further advance of brush |29 of switch ||3. As brush i2@contacted the second and fourth terminals in its advance to the thterminal the ground on the brush short-circuited the battery suppliedthrough resistance to the windings of the composite signaling relay H2thereby transmitting two signal pulses to the step-oy-step end of thetoll trunk circuit.

In response to the two signal pulses just referred to, the step-by-stepend of the trunk shown in Fig. 2 functions in a manner identical withthat previously set forth in connection with the transmission ci thecoin collect signal except that in this instance the two pulses receivedfrom the toll switchboard end of the trunk cause brush 2i@ of switch Zitto advance to the second terminal of the associated bank instead of tothe third terminal as was the case where three signal pulses werereceived in connection with coin collection.

Upon the subsequent recperation of relays 26| and 2&2 following thetransmission of the coin return signal from the toll end of the trunkrelay 22'5 operates in a circuit traceable from battery through itswinding, second terminal and brush 2li! of switch 2|8, back contact ofrelay 225, lower back contact of relay 2|?, and over the front Contactof relay 262 to ground over conductor 2i@ from the toll selectorcircuit. Relay 2Q? performs the same functions in connection with coinreturn as hereinbefore set forth for relay 26B in connection with coincollection eX- cept that positive coin return potential, through lamp22s and over the upper inner iront contact of relay is connected to thewinding of relay 23@ and thence to the subscrbers line instead of' thenegative coin collect potential which was connected to the line whenrelay 208 operated. Relays 23o, 252 and 233 and interrupters 23| and 23eperform functions identical with those set forth under the descriptionof coin collection except that pulses of negative potential areconnected to the line, under control or" interrupter 23 and relays 232and 233, to effect the return of the coin or coins deposited at stationS.

The release of the coin return key H8 by the toll operator opens thecircuit through the windings of relays |33 and E3@ both of which releaseand in turn release relay |31. Relay |25 thereupon releases and operatesrelay 12d over its back contact and over the upper front Contact oforf-normal springs |39. From this point on the signaling portion of thecircuit' at both ends of the toll trunk restore to their normalcondition in the manner previously described in connection with therestoring of these circuits at the conclusion of coin collection.

What is claimed is:

l. In a selective signaling system, a transmitting station, a receivingstation, a line therebetween, a local circuit closer at the transmittingstation, means responsive to operation of said circuit closer fortransmitting a predetermined number of electrical impulses to said lineand responsive to release of said closer for transmittinganotherpredetermined number of impulses, means at the receiving stationresponsive to said first predetermined number of impulses for operatingsaid responsive device and responsive to said second predeterminednumber of impulses' for releasing the=device.

2. VIn a remote control signalingV system, a line, a circuit closer and'an impulse transmitting means at one end of the line, said impulsemeans being arranged to respond to operation of said closer to transmita. predetermined number of electrical impulses to said line and to alsotransmitl a predetermined number of impulses when said closer isrestored, impulse receiving and translating means and aneleetroresponsive de-V vice atY the other end of said line,` saidreceiving and translating means being responsive to said firstpredetermined number of impulsesvtc operate and hold operated saiddevice and also responsive to said second predetermined num ber ofimpulses to release said device.

3. In a remote control signaling system, a line, a key at one end of'the line and a relay at the otherV end of the line, impulsetransmitting means at the rst end of the line and impulse receiv- Vingmeans at the second end of the line, said impulse transmitting meansbeing so arranged that operation of said key will cause said means totransmit a predetermined number of electrical impulses over said line,and release or said key will cause the same means to transmit anotherpredetermined number of impulses, and said receiving means beingarranged to respond to said impulses transmitted when the key isoperated to operate said relay and to respond to the .impulsestransmitted when the key is released to restore said relay.

4. In a remote control selective signaling system, a line, a pluralityof keys at one end .of the lineV anda plurality of corresponding relaysatV the other end of the line, Vimpulse transmitting Ymeans at the rstend of the line, and impulse receiving means at the other'end of theline,v

said impulse transmittingY means being so arranged that operation of anykey Will cause said means to transmit a predetermined characteristicnumber of electrical impulses over said line depending on the keyoperated and release of said key will cause the same means totransmitanotlier predetermined number of impulses, and said receivingmeans being arranged to respond to said impulses transmitted when thekey is operated to operate the relay corresponding to the operated keyand to'respond to the impulses transmitted when the key is restored torelease the relay.

5. In a remote control selective signaling tele- V10 phone system, anoperators position, an automatic exchange, a trunk line extendingtherebetween, a line relay'in said trunk line at the auto` matic end ofthe line and adapted to control selective switchy mechanism at saidautomatic exchange toselectively extend lthe trunk line to a desiredcalled line, a cordcircuit including a dial at SaidOperatOrs positionfor controlling l said line relay, a plurality of functional relays atthe automatic end of` said line,Y each relay being adapted to perform adiierent specific function, a key associatedV with theV cord individualto each of said functional relays, means' associated with the operatorsend of said trunk line and responsive to the operation of any one ofsaid keys, when said cord, circuit is connected to said trunk line, tomomentarily release and operate said line relay a predeterminedcharacteristic number of times depending o n the key operated and tomomentarily releasev said line relay once when any operated one ofsaidkeys is released, and means at the automatic end of said trunk lineresponsive to said predetermined v number of release and closureoperations of said line relay yoccasioned by the operation ofarvdistinctive one of said keys tok operate the corresponding functionalrelay, said'means at the automatic end of the trunk linebeing'alsorensponsive to said single momentary release ofthe line relay when akeyV is released at lthe op-` erators position to release the operatedfunctional. Y

- THOMAS H.- NEELY.

